Drive device

ABSTRACT

A drive device includes a motor having two sets of winding wires, a controller coaxially disposed with the motor for controlling the motor, and a connector for connecting the controller to an external connector. The controller has a first system control unit for controlling power supplied to one set of winding wires and a second system control unit for controlling power supplied to the other set of winding wires. The connector has a first positive electrode terminal and a first negative electrode terminal for power supplied to the first system control unit, and a second positive electrode terminal and a second negative electrode terminal for power supplied to the second system control unit. A portion of a planar face of the first positive electrode terminal is positioned to overlap a portion of a planar face of the first negative electrode terminal, and a portion of a planar face of the second positive electrode terminal is positioned to overlap a portion of a planar face of the second negative electrode terminal.

CROSS REFERENCE TO RELATED APPLICATION

The present application is based on and claims the benefit of priorityof Japanese Patent Application No. 2018-075411, filed on Apr. 10, 2018,the disclosure of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a drive device for driving an electricmotor.

BACKGROUND INFORMATION

An integrally packaged motor and controller drive device may include anelectric motor and a controller for controlling the electric motorpackaged together as a single, integral device (e.g., in one housing).Problems may arise when additional controllers are added to such a drivedevice. As such, drive devices are subject to improvement.

SUMMARY

The present disclosure describes a drive device that limits and/orprevents increases in the size (e.g., diameter) of the drive device andlimits and/or prevents increases in noise when additional connectors andterminals are added to the drive device.

BRIEF DESCRIPTION OF THE DRAWINGS

Objects, features, and advantages of the present disclosure will becomemore apparent from the following detailed description made withreference to the accompanying drawings, in which:

FIG. 1 illustrates a configuration of an electric power steeringapparatus;

FIG. 2 is a vertical cross-sectional view of the drive device;

FIG. 3 is a cross-sectional view along a line III-III in FIG. 2;

FIG. 4 is a schematic diagram of a polyphase coaxial motor;

FIG. 5 is a schematic diagram of the drive device in a first embodimentof the present disclosure;

FIG. 6 is a control block diagram of the drive device in the firstembodiment;

FIG. 7 is a top view of the drive device in the first embodiment takenalong an arrow VII in FIG. 2;

FIG. 8 is a top view of a controller and a connector in the firstembodiment;

FIG. 9 is a top view of the connector in the first embodiment;

FIG. 10 is a top view of the controller in the first embodiment showingterminal groups of the connector;

FIG. 11 is a front view of the controller and power supply terminals ofthe connector in the first embodiment taken along an arrow XI in FIG.10;

FIG. 12 is a top view of the drive device in the first embodiment withan external connector in a non-engaged state;

FIG. 13 is a side view of the drive device in the first embodiment withthe external connector in the non-engaged state taken along an arrowXIII in FIG. 12;

FIG. 14 is a top view of the drive device in the first embodiment withthe external connector in a locked/engaged state;

FIG. 15 is a side view of the drive device in the first embodiment withthe external connector in a locked/engaged state taken along an arrow XVin FIG. 14;

FIG. 16 is a top view of a connector in a second embodiment of thepresent disclosure;

FIG. 17 is a top view of the controller in the second embodiment showingterminal groups;

FIG. 18 is a top view of a connector in a third embodiment of thepresent disclosure;

FIG. 19 is a top view of the controller in the third embodiment showingterminal groups of the connector;

FIG. 20 is a vertical cross-sectional view of the drive device in afourth embodiment of the present disclosure; and

FIG. 21 is another vertical cross-sectional view of the drive device inthe fourth embodiment taken along a line XXI-XXI in FIG. 20.

DETAILED DESCRIPTION

An integrally packaged motor and controller drive device includes anelectric motor and a controller for controlling the electric motorpackaged together as a single, integral device in a single housing. Suchdrive devices may be used in an electric power steering apparatus. Inthis drive device, the motor has two sets of winding wires, and thecontroller has two inverters corresponding to the two sets of windingwires (i.e., windings). The controller includes a connector for a powersupply terminal and a connector for a signal terminal.

When an additional controller is added to the drive device, anadditional power supply connector is added to the drive device forsupplying power to the additional controller. Consequently, extra spaceis required to accommodate the increased number of terminals and theoverall diameter of the drive device or controller may need to beincreased as a result. Adding additional connectors and terminals mayconsequently increase the loop area size of the power supply line andsuch an increase in loop area size may cause an increase in noise on thesignal line.

The embodiments are described with reference to the drawings. In thefollowing embodiments, like elements and features among the differentembodiments use the same reference numerals, and a repeat description ofthe like elements and features may be omitted from the description ofthe latter embodiments.

The drive devices described in the embodiments can be applied to anelectric power steering apparatus of a vehicle, and output a steeringassist torque.

A configuration of the electric power steering apparatus 90 is describedwith reference to FIG. 1. The electric power steering apparatus 90serves as a base, to which the device drivers in each of the embodimentsmay be applied. FIG. 1 shows an overall configuration of a steeringsystem 99 including an electric power steering apparatus 90. Althoughthe electric power steering apparatus 90 shown in FIG. 1 is a rackassist-type, the apparatus 90 is also applicable to a column assist-typeelectric power steering apparatus.

The steering system 99 includes a steering wheel 91, a steering shaft92, a pinion gear 96, a rack shaft 97, wheels 98, and the electric powersteering apparatus 90. The steering shaft 92 is connected to thesteering wheel 91. The pinion gear 96 is disposed at an end of thesteering shaft 92 and engages with the rack shaft 97. Wheels 98 areattached at both ends of the rack shaft 97 via a linkage such as tierods. When a driver of the vehicle rotates the steering wheel 91, thesteering shaft 92 connected to the steering wheel 91 rotates. Therotational motion of the steering shaft 92 is converted into a linearmotion by the pinion gear 96 to linearly move the rack shaft 97. Thepair of wheels 98 is steered to an angle corresponding to thedisplacement amount of the rack shaft 97.

The electric power steering apparatus 90 includes a steering torquesensor 93, a control unit 10, a motor 80, and a speed reducer 94. Thesteering torque sensor 93 is provided at an intermediate portion of thesteering shaft 92, and detects a steering torque of the driver. As shownin FIG. 1, the duplexed steering torque sensor 93 may include a firsttorque sensor 931 to detect a first steering torque trq1 and a secondtorque sensor 932 to detect a second steering torque trq2 in a duplexedor redundant manner. In alternative configurations where the steeringtorque sensor is not provided redundantly, a single detected value ofone steering torque trq may be used.

The control unit 10 obtains the steering torques trq1, trq2 detected bythe steering torque sensor 93, and the electric angles θ1, θ2 of themotor 80 detected by a rotation angle sensor (not shown). The controlunit 10 controls the drive of the motor 80 to generate a desired assisttorque based on information such as the electric angles and the motorcurrent detected inside the control unit 10. The assist torque outputfrom the motor 80 is transmitted to the rack shaft 97 via the speedreducer 94.

The control unit 10 is integrally formed on one side motor 80 (e.g., atone end of the motor 80 along the longitudinal axis of the motor 80).The motor 80 and the control unit 10 are part of a drive device 1. Thedrive device 1 is an integrated motor/controller-type drive device 1. Inthe embodiment shown in FIG. 1, the control unit 10 is disposedcoaxially with the motor 80 on the side of the motor 80 that is oppositeto the output side of the motor 80 (i.e., opposite the output shaft ofthe motor 80). In other embodiments, the control unit 10 may be arrangedcoaxially with the motor 80 on the output shaft side of the motor 80.

With references to FIGS. 2 and 3, the motor 80 is a three-phasebrushless motor that includes a stator 840 and a rotor 860 housed withina housing 830. The stator 840 has a stator core 845 fixed to the housing830 and two sets of three-phase winding wires 801, 802 assembled to thestator core 845. Three lead wires 851, 853, 855 (shown partially in FIG.3) are respectively connected to, and extend from, the three phases ofwinding wires (e.g., U-phase, V-phase, and W-phase, shown in FIG. 4)that form the first set of winding wires 801. Similarly, three leadwires 852, 854, 856 (shown partially in FIG. 3) are respectivelyconnected to, and extend from, the three phases of the winding wiresthat form the second set of winding wires 802.

The rotor 860 has a shaft 87 supported by a rear bearing 835 and a frontbearing 836, and a rotor core 865 into which the shaft 87 is fitted. Therotor 860 is disposed inside the stator 840 and rotates relative to thestator 840. A permanent magnet 88 is attached at one end of the shaft87.

The housing 830 has a cylindrical case 834, a rear frame end 837 at oneend of the case 834, and a front frame end 838 at the other end of thecase 834. The rear frame end 837 and the front frame end 838 arefastened to each other by bolts or like fasteners (not shown). The leadwires 851-856 of each of the winding sets 801 and 802 are inserted intoa lead wire insertion hole 839 in the rear frame end 837 and connectedto the control unit 10.

As shown in FIG. 4, the sets of winding wires 801 and 802 are arrangedat a common stator core with an electric angle of 30 degrees (i.e.,shifted 30°) between wires of the same phase among the sets of windingwires 801 and 802. For example, the wire V1 corresponding to the V-phasein the first winding wire set 801 is shifted 30 degrees relative to thewire V2 corresponding to the V-phase in the second winding wire set 802.

First Embodiment

Next, the configuration of the drive device 1 of the first embodiment isdescribed with reference to FIGS. 2 to 15. As shown in FIGS. 2 and 3,the control unit 10 includes a controller 20, a cover 21 covering thecontroller 20, a connector part 35 for connecting the controller 20 tothe external connectors 161 and 162 on the external cables 191 and 192,as shown in FIG. 1. The cover 21 is fixed to the connector part 35 by ascrew 155, and protects the control portion 20 from external impact andprevents the ingress of dust, water, and like solids/liquids into thecontrol portion 20. The cover 21 may be fixed to the connector part 35by a fastener other than a screw. For example, the cover 21 may be fixedto the connector part 35 by an adhesive.

The controller 20 includes a heat sink 245 fixed to the rear frame end837, substrates 230 and 235 and power modules 241 and 242 respectivelyfixed to the heat sink 245, and various electronic components mounted onthe substrates 230 and 235. In FIGS. 2 and 3, electronic components arenot shown in the illustration. The electronic components are describedlater with reference to FIGS. 5 and 6. The power modules 241 and 242have switching elements and are connected to the lead wires (e.g., 852and 856) of the respective winding sets 801 and 802. The heat sink 245is provided under the cover 21 on the inside of the drive device 1 at aposition between the rear frame end 837 and the connector part 35, andis fixed by a screw 156. The substrate 230 is provided at a positionfacing the rear frame end 837. The substrate 235 is provided at aposition facing the connector part 35. On the substrates 230, 235, twosystems of electronic components may be independently provided for eachsystem to realize a redundant configuration.

FIG. 5 shows a circuit configuration of the drive device 1. Thecontroller 20 is a dual-system motor control device that has twoinverters 601 and 602 that function as “power converters,” two computers401 and 402, and the controller 20 is connected to the two sets ofwinding wires 801 and 802 in the motor 80. In the dual system, thecombination of the elements including the set of winding wires, theinverter, and the computer may be referred to as a “system,” i.e., oneset of components in the dual, redundant configuration. For example, theinverter 601, the computer 401, the winding wires 801, and the otherelectronic elements associated with these components may be referred toas a system.

To distinguish between the different systems in the description, “first”or “first system” may be added to the components and/or signals of thefirst system, and “second” or “second system” may be added to thecomponents and/or signals of the second system. For elements common toboth systems, or when describing components in general, i.e., when thereis no need to distinguish between the first and second systems, the“first” and “second” identifiers may be omitted Except for switchingelements, e.g., 611-616 and 621-626, “1” is added to the end of thereference characters of the components or signals used to describe thefirst system, and “2” is added to the end of the reference characters ofthe components or signals used to describe the second system.

The controller 20 includes the first and second inverters 601 and 602,the first and second power supply relays 141 and 142, the first andsecond rotation angle detection units 251 and 252, and the first andsecond computers 401 and 402. In the first embodiment, electric power issupplied to the first system from the first power source 111 andsupplied to the second system from the second power source 112.

Two sets of six switching elements 611 to 616 and 621 to 626 such asmetal-oxide semiconductor field-effect transistors (MOSFETs) arebridge-connected to serve respectively as the first inverter 601 and thesecond inverter 602. The first inverter 601 performs a switchingoperation according to a drive signal from the first computer 401,converts a direct current (DC) power of the first power source 111, andsupplies the electric power to the first set of winding wires 801. Thesecond inverter 602 performs a switching operation according to a drivesignal from the second computer 402, converts a DC power of the secondpower source 112, and supplies the power to the second set of windingwires 802.

The power supply relay 141 is included on the power supply line at theinput of the first inverter 601 and the power supply relay 142 isincluded on the power supply line at the input of the second inverter602. The first and second power supply relays 141 and 142 shown in FIG.5 both include a protection function that protects against a reverseconnection of the power supply. The protection function in each of thepower supply relays 141 and 142 is realized by a series connection oftwo switching elements having parasitic diodes opposite to each other.However, in place of the protection function, the power supply relays141 and 142 may include one switching element or be provided asmechanical relays that do not include the reverse connection protectionfunction. A capacitor 281 is included at the input sections of the firstinverter 601 and a capacitor 282 is included at the input section of thesecond inverter 602. The capacitors 281 and 282 respectively smooth theelectric power input from the first and second power supplies 111 and112, and limit and/or prevent noise caused by the switching of theswitching elements 611-616 and 621-626 in the first and second inverters601 and 602. Each of the capacitors 281 and 282 may form a filtercircuit together with an inductor (not shown) in their respectivesystems. That is, the first system may have a filter circuit with thefirst capacitor 281 and the second system may have a filter circuit withthe second capacitor 282.

The first rotation angle detection unit 251 detects an electric angle θ1of the motor 80 and outputs the electric angle θ1 to the first computer401. The second rotation angle detection unit 252 detects an electricangle θ2 of the motor 80 and outputs the electric angle θ2 to the secondcomputer 402. The first rotation angle detection unit 251 has a powersupply line and a signal line that are separate and distinct from thepower supply line and the signal line of the second rotation angledetection unit 252.

The first computer 401 calculates a drive signal for instructing theoperation of the first inverter 601 based on feedback information suchas the steering torque trq1, an electric current Im1, and the electricangle θ1. The second computer 402 calculates a drive signal forinstructing the operation of the second inverter 602 based on feedbackinformation such as the steering torque trq2, an electric current Im2,and the electric angle θ2.

FIG. 6 shows a control configuration of the drive device 1. In FIG. 6,the first system and the second system are composed of two completelyindependent sets of elements, and have a redundant configuration, i.e.,are configured as a “whole duplexed system.”

In the controller 20, electronic components of the first system forcontrolling the power supply to the winding wires 801 make up a firstsystem control unit 201, and electronic components of the second systemfor controlling the power supply to the winding wires 802 make up asecond system control unit 202.

The connector part 35 includes a first system connector 351 having afirst system terminal group connected to the first system control unit201, and a second system connector 352 having a second system terminalgroup connected to the second system control unit 202.

The first system terminal includes first power supply terminals (e.g.,first power supply bus bars) 121 and 131 for supplying power to thefirst system control unit 201, a first vehicle communication terminal311 for inputting a signal to the first system control unit 201, and afirst torque signal terminal 331. The second system terminal includessecond power supply terminals (e.g., second power bus bars) 122 and 132for supplying power to the second system control unit 202, a secondvehicle communication terminal 312 for inputting a signal to the secondsystem control unit 202, and a second torque signal terminal 332.

The first power supply terminals 121 and 131 are connected to the firstpower source 111. Electric power from the first power source 111 issupplied to the first set of winding wires 801 via the first powersupply terminals 121 and 131, the first power supply relay 141, and thefirst inverter 601. Electric power from the first power source 111 isalso supplied to the first computer 401 and the sensors of the firstsystem.

The second power supply terminals 122 and 132 are connected to thesecond power source 112. Electric power from the second power source 112is supplied to the second winding set 802 via the second power supplyterminals 122 and 132, the second power supply relay 142, and the secondinverter 602. Electric power of the second power source 112 is alsosupplied to the second computer 402 and the sensors of the secondsystem.

When a Controller Area Network (CAN or CAN bus) is redundantly providedas a vehicle communication network, the first vehicle communicationterminal 311 is connected at a position between a first CAN 301 and thefirst vehicle communication circuit 321. The second vehiclecommunication terminal 312 is connected at a position between a secondCAN 302 and the second vehicle communication circuit 322. When a CAN isnot provided redundantly, the vehicle communication terminals 311 and312 of the two systems may be connected to the same CAN. A vehiclecommunication network using a communication standard other than CAN maybe used. For example, a network standard such as CAN with Flexible Datarate (CAN-FD) or FlexRay may be used.

The first torque signal terminal 331 is connected at a position betweenthe first torque sensor 931 and a first torque sensor input circuit 341.The first torque sensor input circuit 341 notifies the first computer401 of the steering torque trq1 sent to the first torque signal terminal331 by the first torque sensor 931. The second torque signal terminal332 is connected at a position between the second torque sensor 932 andthe second torque sensor input circuit 342. The second torque sensorinput circuit 342 notifies the second computer 402 of the steeringtorque trq2 sent to the second torque signal terminal 332 by the secondtorque sensor 932.

The computers 401 and 402 can mutually transmit and receive informationto and from each other by performing inter-computer communication. Whenan abnormality occurs in one of the two systems, the controller 20 cancontinue the motor control by using the normal functioning system (i.e.,by using the other system that is operating normally withoutabnormalities).

FIGS. 2, 3, 7 to 11 show the configuration of the connector part 35. Thefollowing description assumes that the drive device 1 is cylindrical inshape. Thus, the following description may describe the geometry of thedrive device 1 and the arrangement, orientation, disposition, andpositioning of the elements, components and features of the drive device1 in terms of a circle (e.g., radial distance). However, the drivedevice 1 is not limited to a cylindrical shape and may be a non-circularshape where accordingly, the circular descriptions may be replaced witha corresponding description based on the shape and the geometry of thedrive device 1 (e.g., replacing the term “radial distance” with a“vector length from a center point to a side of the drive device” in adrive device with a rectangular shaped cross section).

In FIGS. 2, 3, 9, and 10, a longitudinal axis of the motor 80 of thedrive device 1 is shown as axis Ax. In FIGS. 9 and 10 showing an axialview, axis Ax is shown as a point where the longitudinal axis Ax of themotor 80 extends into and out of the drawing sheet. In FIGS. 2 and 3showing a cross-sectional view, the axis Ax is shown as a line thatextends from the top to bottom of the drawing sheet. The axis Ax isdisposed centrally within the drive device 1. A direction extendingorthogonally from the axis Ax may be described as a “radial direction”or “radially,” and a direction running parallel to the axis Ax may bedescribed as an “axial direction” or “axially.”

As shown in FIGS. 2, 3, 7, 8, and 9, the connector part 35 includes abase portion 350, the connectors 351 and 352, the power supply terminals131 and 132, the first and second vehicle communication terminals 311and 312, and the first and second torque signal terminals 331 and 332.The first vehicle communication terminal 311 and the first torque signalterminal 331 may each be referred to as a “first signal terminal” (e.g.,the first signal terminal 311), and the second vehicle communicationterminal 312 and the second torque signal terminal 332 may each bereferred to as a “second signal terminal.” The base portion 350 is fixedto the heat sink 245 by a screw 157. The connectors 351 and 352 extendaxially from the base portion 350 and further through an opening part211 of the cover 21.

The first system connector 351 houses and holds the first power supplyterminals 121 and 131, the first vehicle communication terminal 311, andthe first torque signal terminal 331. The second system connector 352houses and holds the second power supply terminals 122 and 132, thesecond vehicle communication terminal 312 and the second torque signalterminal 332. The insertion and removal (i.e., pull-out) direction ofthe first system connector 351 and the external connector 161 is in theaxial direction, and is the same as the insertion/removal direction ofthe second system connector 352 and the external connector 162. Theinsertion/removal direction refers to the direction wheninserting/pulling out (i.e., removing) the external connector into/fromthe connectors 351 and 352. The insertion/removal direction coincideswith the direction or orientation of a mouth/face of the connectors 351and 352. The mouth of the connector is a mouth at the tip of theconnectors 351 and 352.

As shown in FIG. 7, the first system connector 351 and the second systemconnector 352 are disposed close to each other, with an interval (i.e.,space) G between the two connectors 351 and 352, where the interval G isshorter than a short-side width W of both connectors. In the firstembodiment, the first system connector 351 and the second systemconnector 352 are arranged side-by-side, with their short sides alignedin a straight line. A plurality of ribs 390 connecting the twoconnectors 351 and 352 are formed at a position between the first systemconnector 351 and the second system connector 352.

As shown in FIGS. 8 to 11, the first power supply terminal includes afirst positive electrode terminal 121 and a first negative electrodeterminal 131. The end portions of these power supply terminals 121 and131 are positioned in the first system connector 351 and extend axiallytoward the mouth of the first system connector 351. In the base portion350, the terminals 121 and 131 may branch/split into a plurality ofbranches so that one branch of each of the terminals 121 and 131 extendstoward the substrate 230 while another branch extends toward thesubstrate 235. The second power supply terminal includes a secondpositive electrode terminal 122 and a second negative electrode terminal132. The end portions of these power supply terminals 122 and 132 arepositioned in the second system connector 352 and extend axially towardthe mouth of the second system connector 352. In the base portion 350,the terminals 122 and 132 may branch into a plurality of branches sothat one branch of each of the terminals 122 and 132 extends toward thesubstrate 230 while another branch extends toward the substrate 235.

In the top view of FIG. 10, where the view is taken along the axis Ax ofthe motor 80, the first positive electrode terminal 121 overlaps aportion of the first negative electrode 131 and the second positiveelectrode terminal 122 overlaps a portion of the second negativeelectrode 132, where the overlapping portions are indicated bycrisscross hatching. The front view of FIG. 11, taken along XI in FIG.10, shows the second positive electrode terminal 122 overlappingportions of the second negative electrode terminal 132.

The positive electrode terminals 121 and 122 and the negative electrodeterminals 131 and 132 are of an electrically conductive material such asmetal, and formed from stamping a flat stock such as a foil or sheetmetal, and then bending the stamped metal terminals 121, 122, 131, and132 into shape. As such, the terminals 121, 122, 131, and 132 may beplanar in shape and have a rectangular-shaped cross-section, where thelong side of the cross-section corresponds to the planar faces orsurfaces of the terminals (e.g., front face, rear face, top surface,bottom surface), and the short side of the cross-section corresponds tothe sides of the terminals. The short side of the cross-sectioncorresponds to the thickness of the material from which the terminalsare stamped. Because the terminals 121, 122, 131, and 132 are formed ofa planar material and bend and branch in different directions, thedrawings (e.g., FIGS. 10 and 11) may illustrate both the faces and sidesof the terminals 121, 122, 131, and 132.

The positive electrodes 121 and 122 may be arranged so that their planarsurfaces (i.e., faces) overlap the planar surfaces/faces of the negativeelectrodes 131 and 132. In the hatched overlap portions of FIG. 10, thehatching shows only the top face of the first positive electrode 121,while the underlying top face of the first negative electrode 131 isobscured from view by the positive electrode 121. Similarly, thehatching for the second positive and negative electrodes 122 and 132only show the top face of the second positive electrode 122, whichoverlies and obscures the view of the top face of the second negativeelectrode 132.

In the first system terminal group and the second system terminal group,corresponding terminals have the same shape. For example, the firstpositive electrode terminal 121 and the second positive electrodeterminal 122 have the same shape, and the first negative electrodeterminal 131 and the second negative electrode terminal 132 have thesame shape. The first system terminal group and the second systemterminal group are also symmetrically arranged relative to the axis Ax.Similarly, the first system connector 351 and the second systemconnector 352 are symmetrical to one another about the axis Ax.

As shown in FIGS. 9 and 10, a substrate connection end 125 of the firstpositive electrode terminal 121 and a substrate connection end 135 ofthe first negative electrode terminal 131 are arranged side by side oneither side of the virtual line L that passes through the axis Ax. Thesubstrate connection ends 125 and 135 are arranged along a straight linethat is orthogonal to the virtual line L. Similarly, a substrateconnection end 126 of the second positive electrode terminal 122 and asubstrate connection end 136 of the second negative electrode terminal132 are arranged side by side on either side of the virtual line L,where the substrate connections 126 and 136 are arranged along astraight line that is perpendicular to the virtual line L. In the firstembodiment, the substrate connection end 125 and the substrateconnection end 135 are arranged side by side on a line tangential to acircle centered on the axis Ax, and the substrate connection ends 126and 136 are arranged side by side on a line tangential to the samecircle centered on the axis Ax.

In the first embodiment, the connectors 351 and 352 and the mouths ofthe connectors have a rectangular shape. That is, each of the connectors351 and 352 has a pair of long sides and a pair of short sides.

As shown in FIGS. 2 and 7, the connectors 351 and 352 have protrusionsor bosses 391 and 392 protruding radially from the short sides of theconnectors 351 and 352.

That is, the protrusions 391 and 392 do not protrude from the long sidesof the connectors 351 and 352, such as in the gap between the connectors351 and 352.

As shown in FIGS. 12 to 15, the external connectors 161 and 162 arefitted to the mouth of the connectors 351 and 352. The externalconnectors 161 and 162 respectively include rotating levers 181 and 182that rotate around and pivot about the protrusions 391 and 392. Theexternal connectors 161 and 162 have cutout grooves 175 and 176 foravoiding interference with the protrusions 391 and 392 when the externalconnectors 161 and 162 are inserted into the connectors 351 and 352. Thelevers 181 and 182 include engagement grooves 185 and 186. Theorientation of the grooves 185 and 186 can change depending on theorientation of the levers 181 and 182, such that the engagement grooves185 and 186 allow the external connectors 161 and 162 to connect to theconnectors 351 and 352 without interfering with the protrusions 391 and392. The levers 181 and 182 can then be rotated after the externalconnectors 161 and 162 connect to the connectors 351 and 352 to changethe orientation of the engagement grooves 185 and 186. As such, theengagement grooves 185 and 186 can be rotated to engage the protrusions391 and 392 after the external connectors 161 and 162 are connected tothe connectors 351 and 352. When performing the installation of thedrive device 1 in a vehicle, a worker can press the levers 181 and 182to initially insert the external connectors 161 and 162 into the mouthof the connectors 351 and 352. As the levers 181 and 182 are pressed,the levers begin to rotate. That is, as the levers 181 and 182 rotatefrom the position shown in FIG. 12 to the position shown in FIG. 14, theexternal connectors 161 and 162 move in the insertion direction. Whenthe levers 181 and 182 are rotated to the position shown in FIG. 14, theengagement grooves 185 and 186 are rotated to a position that isperpendicular to the insertion/removal direction, to prevent theexternal connectors 161 and 162 from falling off or disengaging from theconnectors 351 and 352. Claws (not shown) may be provided on theexternal connectors 161 and 162, together with holes (not shown) on thelevers 181 and 182 to lock the levers 181 and 182 after rotating to theposition shown in FIG. 14. When the levers 181 and 182 rotate from theposition shown in FIG. 13 to the position shown in FIG. 15, theengagement grooves 185 and 186 engage with the protrusions 391 and 392.The protrusions 391 and 392 limit the travel of the levers 181 and 182of the external connectors 161 and 162 and may be used to lock thelevers 181 and 182.

As shown in FIGS. 13 and 15, a space 51 is included on one side of theconnector 351 to allow the first lever 181 to rotate to engage anddisengage the protrusion 391 of the first system connector 351 (i.e., toswitch between an engaged state in FIG. 15 and a disengaged state inFIG. 13). Similarly, a space S2 is included on one side of the connector352 to allow the second lever 182 to rotate to engage and disengage theprotrusion 392 of the second system connector 352. In other words, thefirst lever 181 used to engage the boss 191 of the first systemconnector 351 is arranged to have an interference-free operation space51 thereabout for moving/switching the lever 181 between an engagementand disengagement state relative to the boss 191. Similarly, the secondlever 182 used to engage the boss 192 of the first system connector 352is arranged to have an interference-free operation space S2 thereaboutfor moving/switching the lever 182 between an engagement anddisengagement state relative to the boss 192. The interference-freespace 51 of the first lever 181 and the interference-free space S2 ofthe second lever 182 are mutually opposite to each other in terms of thearrangement positions of the first lever 181 and the second lever 182.

(Effects)

As described in the first embodiment above, the connector part 35includes the first positive electrode terminal 121 and the firstnegative electrode terminal 131 for supplying power to the first systemcontrol unit 201, and the second positive electrode terminal 122 and thesecond negative electrode terminal 132 for supplying electric power tothe second system control unit 202. A portion of a planar face of thefirst positive electrode terminal 121 is arranged to overlap a portionof the planar face of the first negative electrode terminal 131.Similarly, a portion of the planar face of the second positive electrodeterminal 122 overlaps a portion of the planar face on the secondnegative electrode terminal 132.

By arranging the faces/surfaces of the positive electrode terminals 121and 122 and the negative electrode terminals 131 and 132 to overlap witheach other, as described above, the power supply terminals can be easilyarranged and rearranged depending on the configuration of the drivedevice 1. For example, if other connectors are included in addition toconnectors 351 and 352, the drive device 1 can easily be reconfigured toaccommodate additional connectors without increasing the overall size(e.g., diameter) of the drive device 1. The advantageous effects of suchan arrangement can be applied to a drive device having a one systemconfiguration. In other words, by using the overlapping arrangement ofthe current embodiment, multiple connectors and multiple systems can beaccommodated within a drive device 1 intended to house only onesystem/connector, without needing to increase the diameter of the drivedevice 1 to house the additional systems and accommodate the additionalconnectors. In addition, by using such an arrangement of the positiveelectrode terminals and the negative electrode terminals, the loop areaof the power supply line can be better limited in size and/or preventedfrom increasing in size. Consequently, the above-described overlappingarrangement of the face surfaces of the positive electrode terminals andthe negative electrode terminals not only limits and/or preventincreases in the overall size (i.e., diameter) of the drive device 1,but also limits and/or prevents noise generation by limiting increasesto the loop size of the power supply line.

The positive electrode terminals 121 and 122 and the negative electrodeterminals 131 and 132 each has a rectangular-shaped cross-section wherethe cross-section includes long sides and short sides of the rectangle.The first positive electrode terminal 121 and the first negativeelectrode terminal 131 are arranged so that the long sides of theircross-sections overlap with each other. The second positive electrodeterminal 122 and the second negative electrode terminal 132 are arrangedso that the long sides of their cross-sections overlap with each other.By positioning the positive electrode terminals 121 and 122 and thenegative electrode terminals 131 and 132 so that their long sidesoverlap with each other, a more effective reduction in noise can berealized.

The first positive electrode terminal 121 and the second positiveelectrode terminal 122 have the same shape. Further, the first negativeelectrode terminal 131 and the second negative electrode terminal 132have the same shape. As such, cost reductions may be realized by usingmultiple components with the same shape.

The first system terminal group and the second system terminal group aresymmetrically arranged with respect to the axis Ax. As such, thefootprint or silhouette of the drive device 1 can be made smaller toreduce the overall volume of the drive device 1 by using such anarrangement of the terminals.

The first system connector 351 and the second system connector 352 aresymmetrically arranged about the axis Ax. As such, thefootprint/silhouette of the drive device 1 can be made smaller to reducethe volume of the drive device 1 by using such an arrangement of theterminals.

The insertion and removal directions of the first system connector 351and the second system connector 352 are in the same, axial direction asthe longitudinal axis Ax of the drive device 1/motor 80. The firstsystem connector 351 and the second system connector 352 are arrangedsuch that the short sides of the connectors/connector mouths are alignedon a straight line, and the length of the gap/space G between theconnectors is smaller than the short side width W of the connectors toposition the connectors 351 and 352 close to one another. The connectors351 and 352 have the protrusions 391 and 392 protruding from the shortsides of the connectors 351 and 352.

That is, the protrusions 391 and 392 do not protrude from the long sidesof the connectors 351 and 352 and are not formed in the gap between theconnectors. In such arrangement, the protrusions 391 and 392 are spacedapart from each other, so that the connectors 351 and 352 can be movedcloser to one another. Thus, the space surrounding a connector forconnecting the connector (i.e., installation space) can be reduced,which in turn reduces the overall body size/volume of the drive device1. Since the protrusions 391 and 392 are separated from each other andmoved to the short sides of the connectors 351 and 352, such anarrangement of the protrusions 391 and 392 frees up space on one of thelong sides of the connectors 351 and 352 for operating the levers 181and 182.

The arrangement of the connectors 351 and 352 may realize additionalspace savings to create a space 51 on one of the long sides of theconnector 351 for operating the first lever 181 and to create a space S2on one of the long sides of the connector 352 for operating the secondlever 182. Such an arrangement of the connectors 351 and 352 improvesthe workspace around the connectors 351 and 352 to improve and ease theconnection of the external connectors 161 and 162 to the connectors 351and 352. Such an arrangement of the connectors 351 and 352 can furtherreduce the overall size/volume of the drive device 1 in an externalconnector-connected state (i.e., reduce the overall size of the drivedevice 1 when the external connectors 161 and 162 are connected to theconnectors 351 and 352).

One or more ribs 390 are formed in the space between the first systemconnector 351 and the second system connector 352 and extend between thelong sides of the connectors 351 and 352 to connect the connectors. Byusing such rib structure 390, the strength of the connector part 35 canbe improved to limit deformations of the connectors 351 and 352. Thearrangement and position of the ribs 390 also eliminate a need foradditional rib structures (e.g., on the other long side of theconnectors 351 and 352), which realizes additional volume reductions tothe drive device 1.

The substrate connection end 125 of the first positive electrodeterminal 121 and the substrate connection end 135 of the first negativeelectrode terminal 131 are arranged along a line that is perpendicularto the virtual line L passing through the axis Ax. Similarly, thesubstrate connection end 126 of the first positive electrode terminal122 and the substrate connection end 136 of the second negativeelectrode terminal 132 are arranged along a line that is perpendicularto the virtual line L passing through the axis Ax in the axial view. Byusing such an arrangement, the power supply terminals 121 and 131 of thefirst system and the power supply terminals 122 and 132 of the secondsystem can be connected to the substrate 235 in a single manufacturingprocess (i.e., in a single manufacturing step). As such, such anarrangement can reduce the overall manufacturing time of the drivedevice 1 to realize additional cost savings by using a more effectivemanufacturing process.

Second Embodiment

The second embodiment is shown in FIGS. 16 and 17. In FIG. 16, one ofthe connectors 361 and 362 is rotated 90 degrees relative to the othersuch that the short sides of the first system connector 361 are parallelto the long sides of the second system connector 362. In thisarrangement, the first system terminal group and the second systemterminal group are not arranged symmetrically with respect to the axisAx. In other words, the first system terminal group and the secondsystem terminal group need not be arranged symmetrically, and the firstsystem connector 361 and the second system connector 362 need not bearranged symmetrically. Except for the arrangement of the connectors 361and 362, the second embodiment has a similar configuration as that ofthe first embodiment, and can achieve the same advantageous effects asthose realized by first embodiment.

Third Embodiment

The third embodiment is shown in FIGS. 18 and 19. In FIG. 18, theconnectors 371 and 372 of a connector part 37 are arranged such that afirst system connector 371 and a second system connector 372 are angledrelative to one another at a predetermined angle. In such anarrangement, the first system terminal group and the second systemterminal group are not arranged symmetrically with respect to the axisAx. In other words, the first system terminal group and the secondsystem terminal group need not be arranged symmetrically, and the firstsystem connector 371 and the second system connector 372 need not bearranged symmetrically. Except for the arrangement of the connectors 371and 372, the third embodiment is configured similar to the configurationof the first embodiment, and can achieve the same advantageous effectsas those realized by the first embodiment.

Fourth Embodiment

The fourth embodiment is shown in FIGS. 20 and 21. In the fourthembodiment, various electronic components of the controller are mountedon one substrate 230. In other words, the substrate of the controllermay be provided as a single, one-piece board. Except for theconfiguration of the substrate 230, the fourth embodiment is configuredsimilar to the configuration of the first embodiment, and can achievethe same advantageous effects as those of the first embodiment.

Other Embodiments

In other embodiments, the power may be supplied by a single power sourcethat branches off to supply power to the individual systems. As such,the teachings of the above-described embodiments can be applied to thepower terminals of a single power source configuration. That is, evenwhen a single power supply is shared by a plurality of systems, a noisereduction effect may be realized by arranging a portion of the planarface of the positive electrode terminal and to overlap with a portion ofthe planar face.

In the descriptions of the first to fourth embodiments, the base portion350 and the connectors 351 and 352 of the connector part 35 aredescribed as being separate structural members from the cover 21. Inother embodiments, the base portion, the connector, and the cover may beformed as a single member, i.e., as a single structure or as one body.In such a configuration, the terminals of the connectors may beconnected to the substrate of the controller, for example, by a pressfitting engagement. Alternatively, the substrate of the controller maybe fixed to the connector, while having the lead wires of the windingset connected to the controller, for example, by press fitting.

In other embodiments, the motor may have two sets of winding wiresarranged in-phase (i.e., in the same phase). The number of phases of themotor is not limited to three, but may be four or more. The motor to bedriven by the drive device is not limited to an alternating current (AC)brushless motor, but may be a brushed direct current (DC) motor. In suchcases, an H bridge circuit may be used as a “power converter.”

In other embodiments, the drive device is not only applicable to anelectric power steering apparatus, but may be applied to other electricmotors.

Although the present disclosure is described by the above embodimentswith reference to the accompanying drawings, it is to be noted thatvarious changes and modifications will become apparent to those skilledin the art, and such changes, modifications, and summarized schemes areto be understood as being within the scope of the present disclosure asdefined by appended claims.

What is claimed is:
 1. A drive device comprising: a motor having a firstset of winding wires and a second set of winding wires; a controllerdisposed coaxially with the motor and configured to control the motor;and a connector configured to connect to an external connector of anexternal cable to form a connection between the controller and theexternal connector, wherein the controller has a first system controlunit and a second system control unit, the first system control unitconfigured to control power supplied to the first set of winding wiresand the second system control unit configured to control power suppliedto the second set of winding wires, and wherein the connector has afirst positive electrode terminal and a first negative electrodeterminal for power supplied to the first system control unit, and asecond positive electrode terminal and a second negative electrodeterminal for power supplied to the second system control unit, andwherein a portion of a planar face of the first positive electrodeterminal overlaps a portion of a planar face of the first negativeelectrode terminal, a portion of a planar face of the second positiveelectrode terminal overlaps a portion of a planar face of the secondnegative electrode terminal, the first positive electrode terminal andthe first negative electrode terminal each have a rectangular-shapedcross-section having a long side and a short side, the long side of thecross-section of the first positive electrode terminal positioned toaxially overlap the long side of the cross-section of the first negativeelectrode terminal when viewed along an axial direction of the motor,and the second positive electrode terminal and the second negativeelectrode terminal each have a rectangular-shaped cross-section having along side and a short side, the long side of the cross-section of thesecond positive electrode terminal positioned to axially overlap thelong side of the cross-section of the second negative electrode terminalwhen viewed along the axial direction of the motor, wherein to axiallyoverlap comprises overlapping in a direction parallel to the axialdirection of the motor.
 2. The drive device of claim 1, wherein thefirst positive electrode terminal and the second positive electrodeterminal have a same shape, and the first negative electrode terminaland the second negative electrode terminal have a same shape.
 3. Thedrive device of claim 2, wherein the connector has a first signalterminal for inputting a signal to the first system control unit and asecond signal terminal for inputting a signal to the second systemcontrol unit, and wherein the first positive electrode terminal, thefirst negative electrode terminal, and the first signal terminal aregrouped together as a first system terminal group, and wherein thesecond positive electrode terminal, the second negative electrodeterminal, and the second signal terminal are grouped together as asecond system terminal group, and wherein the first system terminalgroup is positioned symmetrically to the second system terminal groupabout an axis of the motor.
 4. The drive device of claim 3, wherein theconnector has a first system connector configured to hold the firstsystem terminal group and a second system connector configured to holdthe second system terminal group, and wherein the first system terminalgroup is positioned symmetrically to the second system terminal groupabout the axis of the motor.
 5. The drive device of claim 4, wherein aninsertion and removal direction of the first system connector and thesecond system connector is in a same direction as the axis of the motor,and wherein the first system connector and the second system connectorare rectangular-shaped connectors having long sides and short sides, andwherein the first system connector is positioned adjacent to the secondsystem connector to include a gap between the first system connector andthe second system connector, and wherein a distance of the gap is lessthan a width of the short sides of the first system connector and thesecond system connector, and wherein one short side of the first systemconnector is aligned with one short side of the second system connectorand another short side of the first system connector aligned withanother short side of the second system connector, and wherein each ofthe short sides of the first system connector has a boss that protrudesaway from the first system connector that engages a lever of theexternal connector, and each of the short sides of the second systemconnector has a boss that protrudes away from the second systemconnector that engages a lever of the external connector.
 6. The drivedevice of claim 5, wherein a first lever to engage the boss of the firstsystem connector is arranged to have an interference-free operationspace thereabout for a switch operation between engagement anddisengagement, a second lever to engage the boss of the first systemconnector is arranged to have an interference-free operation spacethereabout for a switch operation between engagement and disengagement,and the interference-free operation space of the first lever and theinterference-free operation space of the second lever are mutuallyopposite to each other relative to arrangement positions of the firstlever and the second lever.
 7. The drive device of claim 4, wherein arib is provided at a position between the first system connector and thesecond system connector for connecting the first system connector andthe second system connector.
 8. The drive device of claim 1, wherein asubstrate connection end of the first positive electrode terminal and asubstrate connection end of the first negative electrode terminal arepositioned along a line that is perpendicular to a virtual line thatpasses through an axis of the motor, and a substrate connection end ofthe second positive electrode terminal and a substrate connection end ofthe second negative electrode terminal are positioned along a line thatis perpendicular to the virtual line.
 9. The drive device of claim 1,wherein the long side of the cross-section of the second positiveelectrode terminal axially overlaps the long side of the cross-sectionof the second negative electrode terminal in a region defined between abase portion of the connector and a substrate of the controller.